1. Field of the Invention
The invention is directed generally to laser technology countermeasures and more particularly to the use of absorption technology in order to counter laser detection systems.
2. Description of the Related Art
Currently, there are a variety of detectors, shields and obscurants that are used to detect and/or counteract or shield the effects of laser-based threats. Laser-based threats are used in a variety of capacities to do everything from locating and destroying tanks, artillery, planes, ships, cargo vans and other targets to temporarily or permanently blinding individuals.
Certain laser warning receivers utilize technology that detects and prioritizes the threat level of a laser-based threat and transmits audible and visual warnings on or through a display. This technology serves to indicate to the crew when a target, such as reconnaissance vehicles, armored personnel carrier or main battle tank has been targeted by the laser-based threat, so that the crew may be able to take evasive action, if necessary. Crewmembers are alerted that an enemy has either completed a firing solution or that a precision-guided munition or beamriding missile is heading for their vehicle. Similarly, laser-warning receivers for aircraft detect laser radiation and use signal processing to determine the type of threat and the direction of its source. These electro-optical countermeasures consist of externally mounted sensor units and an inboard interface unit comparator and associated test equipment.
Further, to protect the eye from laser irradiation in the visible to near-IR region, technology has been developed in the form of filter inserts for soldiers' eyewear, also called ballistic and laser protective spectacles (BLPS). The BLPS are dye-filled polycarbonate plastic filters which will protect eyesight against low-energy lasers, specifically the two or three wavelengths used by common range finders and target designators based on Nd:YAG and ruby lasers. The BLPS will not give protection against frequency-agile low energy laser weapons. The filters can provide up to three notches before reception is impaired. To protect thermal imagers from laser irradiation in the far IR spectral region, a filter is employed in front of the sensitive detectors.
Other laser-based threat protection mechanisms include the use of organic absorption dyes to absorb the laser radiation, reflection of the laser radiation using optical coatings or other effects that alter the reflective properties of an intended target's surface, and the blocking of specific wavelengths.
Finally, in certain situations, attenuative properties of smoke, dust, dirt and other particulates allow it to serve as a passive defense against blinding laser weaponry. Large-area smoke generation provides a means for continuous protection for forward elements of U.S. combat forces.